Horrifying creatures have always existed on Innistrad. The humans of this world have always relied on their faith to shield them from vampires and werewolves, spirits and ghouls. But of late, the holy wards and runes have begun to fail. The protection of travelers' shrines and rustic prayers grows weak. The spells of vampire slayers and wolf hunters are no longer proof against the creatures that prowl the shadows. The Lunarch, head of the revered Church of Avacyn, knows what the village priests whisper: that the archangel Avacyn has abandoned Innistrad.

Few know why prayers to Avacyn have gone unanswered, but the consequence is clear to all—the old ways no longer carry the power they once had. In her unexplained absence, the power of Avacyn's influence fades, and the power of Innistrad's fiendish ilk grows. The aristocratic vampire families hunt peasant blood for sport and sustenance. Packs of snarling werewolves ravage caravans and villages. Geists float from their tombs and haunt cobblestone alleyways and ancient manors. The unhallowed dead feed their relentless hunger, roused by forbidden magic or stitched together by the inventions of brainsick alchemists. No longer held back by Avacynian magic, the supernatural horrors of the world are now free to prey on humanity.

Because of the renewed danger, traditions have begun to change across the four provinces of the known world. Stensian shopkeepers close their doors at nightfall. Travelers avoid the grave-riddled lowlands of Nephalia and the mist-laden woods of Kessig. Parish priests, wolf hunters, and the holy warriors known as cathars carry silver with them at all times. Even in the province of Gavony, seat of the Church, the shadows crawl with cults and conspirators.

Still, there are those who strike back against the forces of night. Armed with knowledge of their foes' vulnerabilities and the residual strength of their faith, fiend hunters venture into the haunted places of the world. Priests and specialized slayers train to face unholy fiends and protect parishes across the countryside. Humanity has lost its guardian angel, but there may yet be hope for those facing the horrors of Innistrad.